Binding energy spectra and orbital momentum distributions of the two most stable conformers of L-alanine are investigated. Molecular properties such as geometry and dipole moments agree well with available experimental and previous theoretical investigations. Dual space analysis is employed to study the binding energy spectra in coordinate space based on B3LYP/TZVP density functional calculations, and the valence orbital momentum distributions based on the plane wave impulse approximation. In the valence space, the HOMO (24a), NHOMO (23a) and orbitals 22a and 18a are selected to study the conformational processes in L-alanine.